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Date: Wed, 23 Apr 2014 01:39:30 +0200
From: Andi Kleen <andi@firstfloor.org>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Brian Gerst <brgerst@gmail.com>, Andrew Lutomirski <amluto@gmail.com>,
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Subject: Re: [PATCH] x86-64: espfix for 64-bit mode *PROTOTYPE*
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> That simply will not work if you can take a #GP due to the "safe" MSR
> functions from NMI and #MC context, which would be my main concern.

At some point the IST entry functions subtracted 1K while the
handler ran to handle simple nesting cases.

Not sure that code is still there.

-Andi